Serial sampling of maize and soja grains imported from Argentina were carried out for five months in order to study the occurrence of Aspergillus species (mainly those of Flavi section). For both kind of grains, ten monthly samples collected from a terrestrial port (Los Andes, Chile) were taken from subsamples transferred in plastic bags and supplied by sanitary control personnel. Grains were cultured in duplicate on Petri dishes by using two media: malt salt agar (AMS)and salt water agar (AAS). All Aspergillus detected were lately transferred in malt agar (AM) and czapek agar added with yeast extract (CYA) to determine its ultimate morphological character,